3beta-hydroxy-4-pregnene derivatives and preparation thereof



United States Patent 3,197,470 3fl-HYDROXY-4-PREGNENE DERIVATIVES AND PREPARATION THEREOF Romano Deghenghi, Westxnonnt, Quebec, and David J.

Marshall, Montreal, Quebec, Canada, assignors to American Home Products Corporation, New York, N.Y., a corporation of Delaware No Drawing. Filed Sept. 26 1%3, Ser. No. 310,476 16 Claims. (Cl. zen-239.55

The present invention relates to SB-hydrOXyl-pregnene derivatives and to intermediates used in their preparation. More specifically it relates to 6u,9a-difluoro- 3,8,1lfl-dihydroxy- 160:,17ce isopropyli-denedioxy-4-pregnen-ZO-one and to its physiologically acceptable esters of the following general structure in therapy have the characteristic structure of A -3- ketones of the natural corticoids. In contradistinction to those known substances,.the compounds of this invention are allylic 3fi-alcohols, or derivatives thereof, and do not possess the A -3-ketone structure of the natural corticoids. Moreover, they possess the surprising andunpredictable advantage of exhibiting undesirable side efiects to a lesser degree than other well-known anti-inflammatory substances. The extent to which they cause reduction in the size and Weight of the thymus gland, deposition of liver glycogen, elevation of blood sugar levels, adrenal atrophy, excretion of sodium and potassium, or protein breakdown is smaller in every instance than that obtained with known anti-inflammatory drugs. In addition the compounds of this invention also show a diminished degree of influence upon the blood picture.

Our preferred method for preparing the compounds of this invention may be described as follows.

17a-bromo-6a-fiuoropregesterone (I), obtained as described by D. J. Marshall in US. Patent No. 2,924,610,

is dehydrobrominate-d by means of lithium chloride in dimethylformamide solution to yield 6a-fiuoro-4,16-pregnadiene-3,20-dione (II), a compound previously also described by R. Deghenghi in Can. J. Chem, vol. 38, page 452 (1960). The latter compound is oxidised by means of permanganate in a bufiered solution to yield 16a,17or.- dihydroxy-6a-fiuoro-4-pregnene-3,ZO-dione (III), a compound previously described by J. Fried, Chem. and Ind, 1961, page 465. Incubation of that latter compound with 3',197,47 Patented July 27, I965 spores of Aspergillus ochraceus and isolation of the product of incubation in the usual manner yields 6a-fluoro- 110t,16cc,17oc trihydroxy-4-pregne'ne 3,20 dione (IV). The corresponding 16a,l7a-isopropylidenedioxy derivative is obtained from that latter compound by treatment With acetone and perchloric acid followed by purification by chromatography, to yield fiot-flllOIO-ild-llYdfOXY- 16a,17u-isopropylidenedioxyl-pregnene-3,20-dione (V). The lla-hydroxy group of the last-named compound is then mesylated in the usual manner by treatment with methanesulfonyl chloride and pyridine to yield 6u-fiuoro- 16a,17c isopro-pylidenedioxy-lla-mesyloxyl-pregnene- 3,20-dione (VI), from which the elements of methanesultonic acid are eliminated bytreatment with sodium acetate in acetic acid, or with lithium bromide in dimethylforxnamide, to yield 6u-fluoro-16u,l7u-isopropylidenedioxy-4,9(l1)-pregnadiene-3,20-dione (VII). The elements of hypobromous acid are added to the latter compound by treating it With perchloric acid and N-bromoacetamide, to obtain 9a-bromo-6a-fiuoro-1IB-hydroxy- 16a,17oc isopropylidenedioxy 4 pregnene 3,20 dione (VIII), and the latter compound is converted to the corresponding 95,11,8-epox-ide by treatment with potassium acetate to obtain 9,8,11/3-epoXy-6a-fluoro-l6u,l7u-isopropylidenedioxy 4 pregnene 3,20 dione (IX). The epoxide ring of the latter compound is opened by means of anhydrous hydrogen fluoride at low temperatures, or by means of aqueous hydrofluoric acid at room temperature, to obtain 6a,9a-difluoro-115-hydroxy-16u,l7a-isopropylidenedioxy-4pregnene-3,ZO-dione (X), from which :,9a difluoro-3[3,1lB-dihydroxy-16a,17ot-isopropylidenedioxy-l-pregnen-ZO-one (XI, R=H) is obtained by selective reduction of the 3-keto group with lithium aluminum tri-t-butoxyhydride at room temperature, in a manner similar to that described by D. J. Marshall in Canadian patent application S.N. 825,294. This procedure is also described in the publication of Marshall et al. in J. Med. Chem., vol. 7, pages 355 to 357. The latter compound may then be converted to the desired esters by treatment with the appropriate acid anhydride or acid halide in the conventional manner.

The above reactions may be schematically indicated by the following formulae in which R is defined as above.

e. 0 CO F if. on l CH3 CHaSO-- \C/I 0 ons (VIII) 17u-bromo-6ot-fluoroprogesterone (US. 2,924,610) (50 g.) dissolved inIOOO ml. DMF was treated with 50 g. lithium chloride on a steam bath under N withstirring, for 3 hours. The cooled mixture was slowly poured into water and the precipitate filtered, washed with water and dried to give a product which was recrystallized from acetone-ether, M.P. 166168 C. e

EXAMPLE H 16a,17a-dihya'roxyfia-fluoro4-pregnene-3,20-dione V A quantity of 31.9 'g. of 6rx-fluoro-4,1-pregnadiener V 3,20-dione was dissolved in 1100 ml. acetone and 7.3 ml. acetic acid. A solution of 16.4 g. of KMnO in 775 ml. acetone and 137 ml. water was poured at 0 C. with stirring into the steroid solution. After 5 minutes, the mixture was filtered through celite and the filtrate diluted with ice water. From the clear solution the product crystallizes in needles. M.P. 195-200 C.

EXAMPLE III 6 a-fluOrOJ 1a,16a,1 7u-trz'hy dr0xy-4-pregnene-3,20 di0ne The product of Example II was incubated with spores of Asperigillus ochraceus and the title compound was isolated in the usual manner. M.P. 221-222 3., [011 '+53.() (1% in chloroform).

. EXAMPLE IV Ot-flllOiO-l1(X-hydl'Oxy-160l,1 7u-isopropylidenedioxy- 4-pregnene-3,20-di0ne V The pure compound, its mother liquor or the crude residue from the fermentation of Example III were dis solved in acetone (7.8 g.) in ml., CHlO (0.2 ml.)

Found: C, 68.61;

EXAMPLE V fli-flllUiO-I 6 (2,1 7 a-isopropy lid enedioxy-l 1 a-m esyloxy- 4-pregncne-3,20-dione The product of Example IV, 840 mg. (2 mmoles) in 10 ml. CH Cl was treated with 1 ml. of pyridine and 0.23 ml. methane-sulfonyichloride at room temperature for 22 hours.

The mixture was diluted with ether, washed with dilute CH1 and NaCHG solution, then with water, to give a residue of colorless crystals suitable for the next step.

A portion was crystallized from methylene dichloridernetbanol to ME. 160-162 C. (dec.) (darkening at 140 C.).

EXAMPLE V1 The crude product from Example V (17.5 g.) was dissolved with warming in 180 cc. acetic acid, 35 g. of sodium acetate were added and the mixture was refluxed under nitrogen for two hours. he usual work-up gave a yellow solid which crystallized from methylene dichloride-methanol to give a crude product, MP. 226 C. (dec.). Several crystaliizations raised the MP. to 252 C.

Alternatively, the same compound could also be obtained by refluxing the lltx-mesylate obtained in Example V with an equal weight of lithium bromide in dimethyl formamide for 2 hours. The product was isolated in the usual manner and crystallized from methylene dichloride-methanol.

EXAMPLE VII The product of Example Vi (115 mg.) was dissolved in 2 ml. methylene dichloride and 5.8 m1. of t-butanol. 0.375 ml. of 70% HCIO in 2.5 ml. B was added, followed by a solution of 50 mg. N-bromoacetamide (NBA) in 2.2 ml. t-BuOH. After stirring at room temerature for 15 minutes, 88 mg. of Na SO in 4 cc. H O

added, the solvent partly removed in vacuo at room temperature, water was added, and the precipitate was filtered and washed to obtain crystals, M.P. 175 C. (dec.).

EXAMPLE V Ill The product from Example V11 (10.0 g.), dissolved in acetone (350 1111.), was refluxed overnight with 24.0 g. of potassium acetate. The acetone was removed in vacuo, the residue diluted with methylene dichloride washed with water and dried to give a crystalline residue which was chromatographed on 350 g. of Flor-isil. Ethyl acetate in benzene (5%) eluted the product M.P. 205209 C. (dec.).

EXAMPLE IX The product of Example VIII (4.965 g.) dissolved in 50 ml. methylene dichloride was dropped with stirring at C. within 15 minutes in a mixture of 20 g.

anhydrous tetrahydroiuran and 10 g. anhydrous hydrogen fluoride. it was kept at 0 C. for 17 hours, poured cautiously into ice-cold bicarbonate solution, and extracted with methylene dichloride to give a yellow residue which was chromatographed on 200 g. Florisil. Ethyl acetate in benzene (4%) eluted the product which after crystallization from acetone ether, had Ml. 264-265 C. (dec.).

Calcd. for C H O F C, 65.73; H, 7.36; F, 8.66. Found: C, 65.81; H, 7.39; F, 8.58. [001 +1273 C. (1% in chloroform), h 233.5 m,u., 6 16,200.

Alternatively, the same compound could also be obtained by stirring an heterogeneous mixture of the 9,11- oxide compound (Example VII) with aqueous hydrofluoric acid (48%) at room temperature for 2 hours and by isolating it in the usual way.

EXAMPLE X The product from Example IX (422 mg.) in 8 ml. tetrahydrofuran was reduced with 725 mg. lithium-aluminum-tri-t-butoxyhydride at room temperature for 4 hours. The residue, after the usual Work up, represented a mixture of the two epimeric 3-alcohols.

Recrystallization from ether gave a product MP. C. (dc-c.) suitable for the next steps.

EXAMPLE XI The crude product of Example X (375 mg.) was acetylated overnight with 1 ml. acetic anhydride and 5 ml. pyridine. The usual work up gave an amorphous product which was chromatographed on 20 g. of silica gel.

Ethyl acetate in benzene (5%) eluted a crystalline fraction which was recrystallized for analysis from ether to MP. 212-213" C. (dec), [06113 +66.9 C. (1% in chloroform) Calcd. for C H O F C, 64.71; H, 7.52; P, 7.87. Found: C, 64.76; H, 7.45; F, 7.89

EXAMPLE Xrr 6oz,9o:-difluoro-35,1Jfi-dihydroxy-I 60;,170t-ZS0P7'0Z7Ylid6218- di0xy-4-pregnen-2O-0ne S-hexanote The product of Example X was treated at room temperature overnight with a molar excess of-hexanoic anhydride in pyridine. The title compound was isolated in the usual manner and purified by chromatography.

EXAMPLE Xlll 60:,9ct-dfflMOfO-3fi,11BdihyliOxy-l6u,1 7oz isopropylidenedioxy-4-preguen-20-0ne 3-cyclopentylpropionate The product of Example X was treated at room temperature with a molar excess of cyclopentylpropiony-lchloride in pyridine for 16 hours.

The product was isolated and purified in the usual manner.

By substituting benzoyl chloride in Example XIII the title compound was similarly obtained.

EXAMPLE XV 6 0L,90t-d z flzioro-3 [3,] J ,B-dihydroxy-J 6 04,1 7 a isopropylidenedioay- I-pregnen-ZO-one 3t-butylacetate The product of Example X was treated with a molar excess of t-butylacetyl chloride in pyridine at room temin which R is selected from the group consisting of hydrogen, lower aliphatic acyl groups containing from two to six carbon atoms, cyclopentylpropionyl, and benzoyl groups.

2. 6x,904 difiuoro 35,115 dihydroxy 160:,l7a isopropylidenedioxy-4-pregnen-ZO-one.

3. 35 acetoxy 604,90: diiiuoro 115 hydroXy- 1604,1704-isopropy1idenedioxy-4-pregnen-20-one.

4. 600,900 difluoro 35,115 dihydroxy 1604,1704 isopropylidenedioxy-4-pregnen-20-one 3-hexanoate.

5. 64;,904 difluoro 35,1115 dihydroxy 1604,1704 isopropylidenedioxy-4-pregnen-20-one 3-t-butylacetate.

6. 604,904-difluoro 35,115 dihydroxy 1604,1704 isopropylidenedioXy=4-pregnen-20one -3-cyclopentylpropionate.

7. 604,904 difiuoro 35,115 dihydroxy 1604,1704 isopropylidenedioxy-4-pregnen-20-one S-benzoate.

8. 604, fluoro 110,160,1704 trihydroxy 4 pregnene- 3,20-dione.

9. 604 fluoro 1104 hydroxy 1604,1704 isopropylidenedioxy-4-pregnene-3,20-dione.

It 604 fluoro 1604,1704 isopropylidenedioxy 1104- mesyloxyi-pregnene-3,20-dicne.

11. 604 fluoro 1604,1704 isopropylidenedioxy 4,9 (11)pregnadiene-3,20-dione.

12. 904 bromo 604 fluoro 115 hydroxy 1604,1704- isopropylidenedioXy-4-pregnene-3,ZO-dione.

13. 95,115 epoxy 604 fiuoro 1604,1705 isopropylidenedioxy-4-pregnene-3,ZO-dione.

14. 601,904 difluoro 115 hydroxy 160:,1700- isopropylidenedioXy-4-pregnene3,2O-dione.

15. A process for the preparation of pregnene derivatives of the formula:

heating 3,20-dione; treating the latter compound with acetone in the presence ofna mineral acid to obtain 64xfluoro-114xhydroxy 1604, 1704 isopropylidenedioxy-4-pre ene-3,20- dione; treating the latter compound with methanosulfonyl chloride and pyridine to obtain 604-tluoro-1604,17a-isopropylidenedioxy t-mesyloxy-4-pregnene 3,20-dione; heating the latter compound with pyridine to obtain 604 fiuoro 1601,1704 isopropylidenedioxy 4,9(11)- pregnadiene3,20-dione; stirring a solution of the latter compound with a mineral acid and an N-bromoamide to obtain 906 bromo 604 fluoro hydroxy 1604,170tisopropylidenedioxy-4-pregnene-3,ZO-dione; heating the latter compound Witn potassium acetate to obtain 95,115- epoXy 604 fiuoro 1604,1704 isopropylidenedioXy-4-pregnene-3,20-dione; treating the latter compound with a reagent selected from the group consisting of anhydrous hydrogen fluoride and aqueous hydrofluoric acid to obtain 641,904 difluoro E 115 hydroxy ;,1704 isopropylidenedioxy -4-pregnene-3,20-dione; and stirring a solution of the latter compound with a solution of lithium aluminum tri-t-butoxyhydride to obtain 604,904-difiuoro-35,115- dihydroxy 1600,170t-isopropylidenedioxy 4 pregnen- .ZO-one.

16. A process for the preparation of pregnene derivatives of the formula:

CH (i=0 0 CH3 HO 4 0 0 CHa /g a a 7 in which R represents a radical selected from the group consisting of acetyl, hexanoyl, t-butylacetyl, cyclopentylpropionyl, and ben zoyl radicals, comprising, heating l7o4-dihydroxy-604-fluoro-4-pregnene-3,2Q-dione; incubatformarnide with lithium chloride to obtain 60L-fl1101'0 4,16-pregnadiene-3,20-dione; treating the latter compound With permanganate in a bufiered solution to obtain 160c- 1704-dihydroxy-604-fiuoro-4-pregnene-3,ZO-dione; incubating that latter compound with spores of Aspergillzzs ochraceus to obtain 6a-fiuoro-1104,l6o4,l7atrihydroxy-4- pregnene-3,20-dione; treating the latter compound with acetone in the presence of a mineral acid to obtain 604- fiuoro 1104 hydroXy 1604,1704-isopropylidenedioXy-4- pregnene-3,20-dione; treating the latter compound with Inethanesulfonyl chloride and pyridine to obtain 604-fluoro- 160;,1704 isopropylidenedioxy 1104-mesyloxy-4-pregnene- 3,20-dione; heating the latter compound with acetic acid and sodium acetate to obtain 604-fluoro-1604,1704iso propy1idenedioXy-4,9 1 1 -pregnadiene-3,20-dione; stirring a solution ofthe latter compound with a mineral acid and an N-bromoamide to obtain 904-bromo-604-fiuoro-115- hydroXy 4 1604,17 04 isopropylidenedioxy-4-pregnene-3,20

dione; heating the latter compound with potassium acetate to obtain 95,115-epoXy-600-fiuoro-1604,170r-isopropylidenedioXy-4-pregnene3,20-dione; treating the latter compound with a reagent selected from the group consisting of anhydrous hydrogen fluoride and aqueous hydrofluoric acid to obtain 604,904-difluoro-115-hydroxy-16a,1704-isopropylidenedioXy-4-pregnene-3,20-dione; stirring a solution of the latter compound with a solution of lithium aluminum tri-t-butoxyhydiide to obtain 604,904-diflu0ro- 35,115 dihydroxy 1604,1704 isopropylidene' dioXy- 4-pregnen-20-one; and treating the latter compound with a reagent selected from the group consisting of acetic anhydride, heXanoic anhydride, t-butylacetyl chloride, cyclopentylpropionyl chloride, and benzoyl chloride, to

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,197,470 July 27, 1965 Romano Deghenghi et al.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4 formula "(X)", for that portion of the formula reading CH 1 CH3 2 read I t i column 7, line 38, for "6a,fluoro" read oa-fluoro column 8, line 43, beginning with "17u-dihydroxy-" strike out all to and including "20dione;" in line 47, and insert instead 17o,-

bromo-ofluoroprogesterone in solution in dimethylformamide with lithium chloride to obtain 6a-f1uoro-4,16-pregnadiene-3,20dione treating the latter compound with permanganate in a buffered solution to obtain 16a,17adihydroxy-afluoro-4-pregnene-3,20- dione;

Signed and sealed this 8th day of February 1966.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. PREGNENE DERIVATIVES OF THE FOLLOWING STRUCTURE 